Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa6b646882b37dc3…

MALICIOUS

PDF

88.0 KB Created: 2021-07-22 17:47:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 02e28f8b0a4946df3457de80a82f2a78 SHA-1: f1fffdff37ec8594912722523a386276516a1d11 SHA-256: aa6b646882b37dc3c4706c9f4c9c06b2894cb072d78d7e19eac6e355fd60dced
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress upload directories and disposable hosting sites, suggesting a phishing or malware distribution scheme. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://etimes.mn/uploads/files/visajeketi.pdf In PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4e0123c34---semibomupujid.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5b480b7b3---xebazixozipod.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/f1ga3nr5fg2774v1mog5m0v5m6/tanovekam.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/4put98lr8jgbcr0eparp7jurk5/68429094763.pdfIn PDF document text
    • http://parisplaza.net/clients/3/35/3561a7ce45da2f2f114a98ea6175a4b1/File/bevukupozok.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f46d44946d---67968928705.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0867bababf---lokerazalasufawarume.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/86491696954.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/d8050b967664561952cdd6fba2dc9e70/kukas.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/qtqafn7d8eqgpillghra2h4lqa/rabisuvulipegitaduwaj.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/kqcdq02c6ag0m2d0t6ebmvg7s0/54086116488.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/10442110533.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608195fe75367---27077020144.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/d79d3d84ec2bc4f78a127ba9e14d57ba/zemuratopadogegeg.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f2545e5946b---watoxovikurive.pdfIn PDF document text
    • https://hunde-katzen.at/soubory/xuwojofudixebov.pdfIn PDF document text
    • http://superlitefan.com/uploads/files/dukakabofab.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/8218485092.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/6a9923f21d0cd8dfc52a4d7d09f7a026/luvevujob.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/simogirotikovokukitin.pdfIn PDF document text
    • http://cesmclassof68cheyennewy.com/clients/82478/File/pakasisabara.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/e40a552c3046823f4a202136fe842325/5287197424.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/5f6372298d04395498dc82e337fc094d/wevopajupalofizaxefa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=difference+between+subject+and+object+in+a+sentencePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CD 10880 bytes
SHA-256: 16368beef0d54ad9e6e72b3c23cbf5a7c00af425729966d10a6b590eaf1eaec1
font_01_sfnt_off00010d27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012539.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12539 16736 bytes
SHA-256: 8a03f75f2ca666457e53a5266d674a82709a144f01973da738c2c0ea83fe59cd